Dalton saw the muscles of Harry’s face quivering, and he noticed a pallor that came for an instant.

“I understand,” he said.  “I had thought of it already.  If a Northern general like Lee or Stonewall Jackson were behind us we might never get back across the Potomac.  It’s somewhat the same position that we were in after Antietam.”

“But we’ve no Stonewall Jackson now to help us.”

Again that lump rose in Harry’s throat.  The vision of the sober figure on Little Sorrel, leading his brigades to victory, came before him, but it was a vision only.

“It’s strange that we’ve not come in contact with their scouts or cavalry,” he said.  “In that fight with Pleasanton we saw what horsemen they’ve become, and a force of some kind must be hanging on our rear.”

“If it’s there, Sherburne and his troop will find it.”

“I think I can detect signs of the enemy now,” said Harry, putting his glasses to his eyes.  “See that hill far behind us.  Can’t you catch the gleam of lights on it?”

“I think I can,” replied Dalton, also using glasses.  “Four lights are there, and they are winking, doubtless to lights on another hill too far away for us to see.”

“It shows that the enemy at least is watching, and that while we may retreat unattacked it will not be unobserved.  Hark! do you hear that, George?  It’s rifle shots, isn’t it?”

“Yes, and a lot of ’em, but they’re a long distance away.  I don’t think we could hear ’em at all if it were not night time.”

“But it means something!  There they go again!  I believe it’s a heavy skirmish and it’s in the direction in which Sherburne rode.”

“The general’s up.  It’s likely that one of us will be sent to see what it’s all about.”

General Lee and his whole staff had risen and were listening attentively.  The faint sound of many shots still came, and then a sharper, more penetrating crash, as if light field guns were at work.  The commander beckoned to Harry.

“Ride toward it,” he said briefly, “and return with a report as soon as you can.”

Harry touched his cap, sprang upon his horse and galloped away.  He knew that other messengers would be dispatched also, but, as he had been sent first, he wished to arrive first.  He found a path among the trees along which he could make good speed, and, keeping his mind fixed on the firing, he sped forward.

Thousands of soldiers lay asleep in the woods and fields on either side of him, but the thud of the horse’s hoofs awakened few of them.  Nor did the firing disturb them.  They had fought a great battle three days long, and then after a tense day of waiting under arms, they had marched hard.  What to them was the noise made by an affair of outposts, when they had heard so long the firing of a hundred and fifty thousand rifles and three or four hundred big guns?  Not one in a hundred stood up to see.